In case a second call is made to
sybase_connect() with the same arguments, no
new link will be established, but instead, the link identifier of
the already opened link will be returned.

The link to the server will be closed as soon as the
execution of the script ends, unless it's closed earlier by
explicitly calling sybase_close().

Parameters

servername

The servername argument has to be a valid servername that is defined
in the 'interfaces' file.

username

Sybase user name

password

Password associated with username.

charset

Specifies the charset for the connection

appname

Specifies an appname for the Sybase connection.
This allow you to make separate connections in the same script to the
same database. This may come handy when you have started a transaction
in your current connection, and you need to be able to do a separate
query which cannot be performed inside this transaction.

new

Whether to open a new connection or use the existing one.

Return Values

Returns a positive Sybase link identifier on success, or FALSE on
failure.

If you are having trouble connecting to your sybase database on unix, try checking that the SYBASE environmental variable is set correctly. I was getting connection errors until I found out that this variable had not been set through the server.

freetds is a great, free tool to access your sybase tables with PHP. The setup can be a bit tricky. Use the following to put the environment variables that you need: <?phpputenv ("SYBASE=/usr/local/freetds");putenv ("SYBPLATFORM=linux");putenv ("LD_LIBRARY_PATH=/usr/local/freetds/lib");putenv ("LC_ALL=default");putenv ('PATH=\"/usr/local/freetds/bin:$PATH\"');putenv ("DSQUERY=SYBASE");?>Even if not using freetds, you'll need those env vars to make any sybase connection work. Another option is to just load them into your box from the command line.